It is well known that a laptop computer or a notebook computer has a flat display apparatus using for example, a liquid crystal display (LCD). The addition of an input function such as a touch sensor to such a display apparatus enables the computer to accept touch input or pen input.
In laptop or notebook computers, a cover unit is attached to a system body in a manner which permits it to be opened or closed, and a display panel is embedded inside of the cover unit. Under this conventional construction, if an input function is added to the display apparatus, touch input or pen input has the disadvantage of difficulty in operation because the opened cover unit is pushed down by an input pen or finger tips.
A manner of construction under which the operability of touch input or pen input is improved is disclosed by Japanese Patent No. 63-39731. In the computer disclosed by this patent, an upper cover inside which a display panel with a transparent tablet is imbedded, is slidably or rotatably attached to the case of the system body. In such a computer, if touch input or pen input is attempted, the upper cover can be placed on the case of the system body with the display panel placed face up in a position in which the upper cover slides to the front end of the case of the system body. Thus, the upper cover would not be pushed down during touch input or pen input operation. However, it is actually difficult to implement a mechanical construction for smoothly sliding an upper cover to the front end of a case of the system body in a portable computer. Further, even if the upper cover smoothly slides to the front end of the case of the system body, a long cable is needed (or space for storing the long cable is needed within the case or the upper cover), to establish electrical connection between the upper cover and the case. It is, therefore, very difficult to utilize the construction described by Patent No. 63-39731 in a portable computer.